The development of energy efficient housing technology and the general reduction in air infiltration and leakage in existing North American housing stock have focused public attention on indoor air quality. In older homes, air infiltration, although uncomfortable and energy inefficient, was usually sufficient to dilute any hazardous pollutants generated within the home. However, with tighter home construction, nature, air leakage has been reduced to a minimum and, as a result, pollutants generated in the home can accumulate to harmful levels unless a controlled ventilation system is installed.
Conventional domestic gas ranges are designed to be vented to the interior of the structure in which they are located. As a result, the combustion products, which include substances such as carbon dioxide, carbon monoxide, nitrogen oxides and uncombusted fuel, are present in the house. Studies of indoor air contaminants have cited gas ranges as a major contributor to indoor air pollution. Although gas ranges are usually installed with a vent hood, capture of the combustion products by the hood is incomplete. In homes of tight construction, a further concern is the potential depletion of indoor oxygen levels resulting from interior air being used to support the combustion process.
Known in the art are gas ranges in which the burners are located beneath a glass ceramic top, for ease of cleaning and for appearance. However, ranges of this design do not provide for sealed combustion as the air required for combustion is drawn from indoors and the combustion products are vented to the indoors as well. Also known are gas ranges in which combustion products are exhausted through holes in the aeration bowl of the top burners via an exhaust manifold. In these devices, it is intended that the bottom of the cooking vessel being used will provide a sealing of the burners for capture of the combustion products. However, with these devices the capture of the combustion products is not complete, as there can be significant leakage of combustion products around the vessel. In addition, the air for combustion is drawn from inside the house.